Fan walls are becoming increasingly popular in commercial and industrial HVAC systems because of their energy efficiency. A fan wall consists of multiple smaller fans, often referred to as fan cubes. The fan cubes are arranged in a modular grid to deliver the required airflow to the unit.
Key Benefits of Fan Walls
Nortek Fan Wall
1. Energy Efficiency
Fan walls operate more efficiently than traditional large fans by using multiple smaller horsepower fans. Each of the smaller fans has a higher efficiency coefficient than the larger fan wheels found in air handlers. This leads to lower connected horsepower and reduces energy consumption, by as much as 7% – 15%.
Additionally, each smaller fan is typically direct-drive. This eliminates the need for belts, lubrication, and spring isolators. This reduces maintenance needs and operational complexity.
2. Noise Reduction
Smaller fans in a fan wall generate less noise and create consistent airflow patterns. The consistent airflow creates less turbulence inside the casing. This makes them ideal for noise-sensitive environments compared to louder, single-fan systems.
3. Improved Airflow Distribution
With larger fans, airflow comes from a single source, which often leads to uneven distribution across the cooling coil. This can be problematic because the coil is designed to operate with a specific airflow, such as 500 feet per minute.
When some areas receive 900 feet per minute and others only 300, the coil cannot function as intended. This leads to reduced cooling performance and poor dehumidification. Fan walls solve this issue by providing consistent airflow across the entire coil due to the number of fans which improves airflow distribution.
4. Redundancy and Reliability
A major benefit of fan walls is their ability to ensure system redundancy. With multiple fans in play, if one fan fails, the system can continue operating without major disruptions. This is a critical feature for facilities where system downtime is not an option, such as hospitals, laboratories, and data centers.
Static Allowance
Static pressure is a function of the fan blade’s tip speed. When airflow (CFM) is reduced in a system with a single large fan, static pressure decreases. If it drops to low this leads to issues like surging. With fan walls, specific fans can be shut off to reduce airflow, while the remaining fans maintain their speed and static pressure. This prevents operational issues and ensures consistent performance.
How To Size A Fan Wall Retrofit
An air handler cabinet often remains structurally sound long after components like fans and coils wear out. This makes it possible to upgrade the system with a new fan wall without replacing the entire cabinet. The modular nature of fan walls allows the individual units to be moved through standard doorways and assembled within the existing cabinet. This eliminates the need for large equipment like cranes. You need to know CFM, static pressure and the interior dimensions of the air tunnel. Then we can run a program that will optimize fan array.
Conclusion
Fan walls deliver superior energy efficiency, reliability, and airflow control. By using multiple smaller, high-efficiency fans, they significantly reduce energy consumption. They also lower maintenance costs, provide consistent airflow distribution and maintain optimal static pressure.
The modular design of fan walls further enhances their appeal. This is especially true in retrofit projects where existing air handler cabinets can be upgraded without structural changes. With added benefits like noise reduction and system redundancy, they provide a robust solution for facilities requiring uninterrupted performance.
Whether you’re designing a new system or retrofitting an existing one, incorporating fan wall technology can improvement efficiency, performance, and longevity.
